This invention relates to the field of magnetic memory disc system. More particularly, this invention relates to the field of purge erasure of data stored on a magnetic memory disc.
This invention was conceived in response to a need for apparatus to swiftly (almost instantaneously) and reliably erase highly sensitive data information. Therefore, this invention will be described in connection with the environment and requirement for purge of classified military data. However, it will be understood that the invention is applicable to and has utility for any requirement for quick and reliable erasure of information stored on a magnetic disc.
Magnetic memory discs are used in a wide range of applications where sensitive information is involved. In many military applications, such as, e.g., fighter aircraft, bombers, tactical ground installations, the magnetic memory disc in a memory system may contain classified information. To avoid the capture and loss of such information by an enemy, there is a need to be able to purge, e.g., quickly erase, the classified information in response to a purge signal.
Purge systems proposed or used in the past for memory systems have undesirable features. For example, with magnetic tape memory systems, a typical prior art purge system has used a phosphorous grenade which is activated by a purge erase signal (which, e.g. could be the signal used to activate the ejection seat on a fighter aircraft). Upon receipt of the activation signal the grenade would ignite and burn up the tape. That phosphorus grendate system has drawbacks, not the least of which is the danger of damage to the memory system per se and physical injury to the pilot from unintended actuation of the grenade.